1. Field of the Invention
The present invention relates to a steering control apparatus and method.
2. Description of the Related Art
A steering control apparatus such as an electric power steering (EPS) has been widely employed in a vehicle because of several factors including spotlighting an environment-friendly aspect and increasing an importance of the fuel-economy of vehicle. Current research for the steering control apparatus has aimed at securing stability in high speed driving, and an automatic steering apparatus such as an active safety system.
A conventional steering control apparatus is an apparatus which aims to assist a steering force in consideration of factors including a velocity and an acceleration of a vehicle, a steering torque of a driver, and the like.
However, the conventional steering control apparatus has a disadvantage in that it fails to provide a suitable steering control signal when the vehicle turns. For example, in situations in which a steering angle is excessive or lacking, a frictional coefficient of a road decreases when the vehicle turns, and a driving force is increased in a rear wheel-driving vehicle, although an abnormal turning state (over-steering or under-steering) has a close relation with the steering control apparatus, the conventional method of controlling the steering apparatus fails to provide an improvement of the above-mentioned problems when the vehicle turns. Especially, a method of suitably controlling the steering apparatus is required because the abnormal turning state of the vehicle becomes a large factor in endangering a vehicle and a human-being when the vehicle turns in an abnormal turning state.